<?php

/**
 *
 * Paris
 *
 * http://github.com/j4mie/paris/
 *
 * A simple Active Record implementation built on top of Idiorm
 * ( http://github.com/j4mie/idiorm/ ).
 *
 * You should include Idiorm before you include this file:
 * require_once 'your/path/to/idiorm.php';
 *
 * BSD Licensed.
 *
 * Copyright (c) 2010, Jamie Matthews
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/**
 * Subclass of Idiorm's ORM class that supports
 * returning instances of a specified class rather
 * than raw instances of the ORM class.
 *
 * You shouldn't need to interact with this class
 * directly. It is used internally by the Model base
 * class.
 */
class ORMWrapper extends ORM
{

    /**
     * The wrapped find_one and find_many classes will
     * return an instance or instances of this class.
     */
    protected $_class_name;

    /**
     * Set the name of the class which the wrapped
     * methods should return instances of.
     */
    public function set_class_name($class_name)
    {
        $this->_class_name = $class_name;
    }

    /**
     * Add a custom filter to the method chain specified on the
     * model class. This allows custom queries to be added
     * to models. The filter should take an instance of the
     * ORM wrapper as its first argument and return an instance
     * of the ORM wrapper. Any arguments passed to this method
     * after the name of the filter will be passed to the called
     * filter function as arguments after the ORM class.
     */
    public function filter()
    {
        $args = func_get_args();
        $filter_function = array_shift($args);
        array_unshift($args, $this);
        if (method_exists($this->_class_name, $filter_function))
        {
            return call_user_func_array(array($this->_class_name, $filter_function), $args);
        }
    }

    /**
     * Factory method, return an instance of this
     * class bound to the supplied table name.
     *
     * A repeat of content in parent::for_table, so that
     * created class is ORMWrapper, not ORM
     */
    public static function for_table($table_name, $connection_name = parent::DEFAULT_CONNECTION)
    {
        self::_setup_db($connection_name);

        return new self($table_name, array(), $connection_name);
    }

    /**
     * Method to create an instance of the model class
     * associated with this wrapper and populate
     * it with the supplied Idiorm instance.
     */
    protected function _create_model_instance($orm)
    {
        if ($orm === false)
        {
            return false;
        }
        $model = new $this->_class_name();
        $model->set_orm($orm);

        return $model;
    }

    /**
     * Wrap Idiorm's find_one method to return
     * an instance of the class associated with
     * this wrapper instead of the raw ORM class.
     */
    public function find_one($id = null)
    {
        return $this->_create_model_instance(parent::find_one($id));
    }

    /**
     * Wrap Idiorm's find_many method to return
     * an array of instances of the class associated
     * with this wrapper instead of the raw ORM class.
     */
    public function find_many()
    {
        $results = parent::find_many();
        foreach ($results as $key => $result)
        {
            $results[$key] = $this->_create_model_instance($result);
        }

        return $results;
    }

    /**
     * Wrap Idiorm's create method to return an
     * empty instance of the class associated with
     * this wrapper instead of the raw ORM class.
     *
     * @return Model
     */
    public function create($data = null)
    {
        return $this->_create_model_instance(parent::create($data));
    }
}

/**
 * Model base class. Your model objects should extend
 * this class. A minimal subclass would look like:
 *
 * class Widget extends Model {
 * }
 *
 */
class Model
{

    // Default ID column for all models. Can be overridden by adding
    // a public static _id_column property to your model classes.
    const DEFAULT_ID_COLUMN = 'id';

    // Default foreign key suffix used by relationship methods
    const DEFAULT_FOREIGN_KEY_SUFFIX = '_id';

    /**
     * Set a prefix for model names. This can be a namespace or any other
     * abitrary prefix such as the PEAR naming convention.
     * @example Model::$auto_prefix_models = 'MyProject_MyModels_'; //PEAR
     * @example Model::$auto_prefix_models = '\MyProject\MyModels\'; //Namespaces
     * @var string
     */
    public static $auto_prefix_models = null;

    /**
     * The ORM instance used by this model
     * instance to communicate with the database.
     */
    public $orm;

    /**
     * Retrieve the value of a static property on a class. If the
     * class or the property does not exist, returns the default
     * value supplied as the third argument (which defaults to null).
     */
    protected static function _get_static_property($class_name, $property, $default = null)
    {
        if (!class_exists($class_name) || !property_exists($class_name, $property))
        {
            return $default;
        }
        $properties = get_class_vars($class_name);

        return $properties[$property];
    }

    /**
     * Static method to get a table name given a class name.
     * If the supplied class has a public static property
     * named $_table, the value of this property will be
     * returned. If not, the class name will be converted using
     * the _class_name_to_table_name method method.
     */
    protected static function _get_table_name($class_name)
    {
        $specified_table_name = self::_get_static_property($class_name, '_table');
        if (is_null($specified_table_name))
        {
            return self::_class_name_to_table_name($class_name);
        }

        return $specified_table_name;
    }

    /**
     * Convert a namespace to the standard PEAR underscore format.
     *
     * Then convert a class name in CapWords to a table name in
     * lowercase_with_underscores.
     *
     * Finally strip doubled up underscores
     *
     * For example, CarTyre would be converted to car_tyre. And
     * Project\Models\CarTyre would be project_models_car_tyre.
     */
    protected static function _class_name_to_table_name($class_name)
    {
        return strtolower(preg_replace(array('/\\\\/', '/(?<=[a-z])([A-Z])/', '/__/'), array('_', '_$1', '_'), ltrim($class_name, '\\')));
    }

    /**
     * Return the ID column name to use for this class. If it is
     * not set on the class, returns null.
     */
    protected static function _get_id_column_name($class_name)
    {
        return self::_get_static_property($class_name, '_id_column', self::DEFAULT_ID_COLUMN);
    }

    /**
     * Build a foreign key based on a table name. If the first argument
     * (the specified foreign key column name) is null, returns the second
     * argument (the name of the table) with the default foreign key column
     * suffix appended.
     */
    protected static function _build_foreign_key_name($specified_foreign_key_name, $table_name)
    {
        if (!is_null($specified_foreign_key_name))
        {
            return $specified_foreign_key_name;
        }

        return $table_name . self::DEFAULT_FOREIGN_KEY_SUFFIX;
    }

    /**
     * Factory method used to acquire instances of the given class.
     * The class name should be supplied as a string, and the class
     * should already have been loaded by PHP (or a suitable autoloader
     * should exist). This method actually returns a wrapped ORM object
     * which allows a database query to be built. The wrapped ORM object is
     * responsible for returning instances of the correct class when
     * its find_one or find_many methods are called.
     */
    public static function factory($class_name, $connection_name = null)
    {
        $class_name = self::$auto_prefix_models . $class_name;
        $table_name = self::_get_table_name($class_name);

        if ($connection_name == null)
        {
            $connection_name = self::_get_static_property($class_name, '_connection_name', ORMWrapper::DEFAULT_CONNECTION);
        }
        $wrapper = ORMWrapper::for_table($table_name, $connection_name);
        $wrapper->set_class_name($class_name);
        $wrapper->use_id_column(self::_get_id_column_name($class_name));

        return $wrapper;
    }

    /**
     * Internal method to construct the queries for both the has_one and
     * has_many methods. These two types of association are identical; the
     * only difference is whether find_one or find_many is used to complete
     * the method chain.
     */
    protected function _has_one_or_many($associated_class_name, $foreign_key_name = null)
    {
        $base_table_name = self::_get_table_name(get_class($this));
        $foreign_key_name = self::_build_foreign_key_name($foreign_key_name, $base_table_name);

        return self::factory($associated_class_name)->where($foreign_key_name, $this->id());
    }

    /**
     * Helper method to manage one-to-one relations where the foreign
     * key is on the associated table.
     */
    protected function has_one($associated_class_name, $foreign_key_name = null)
    {
        return $this->_has_one_or_many($associated_class_name, $foreign_key_name);
    }

    /**
     * Helper method to manage one-to-many relations where the foreign
     * key is on the associated table.
     */
    protected function has_many($associated_class_name, $foreign_key_name = null)
    {
        return $this->_has_one_or_many($associated_class_name, $foreign_key_name);
    }

    /**
     * Helper method to manage one-to-one and one-to-many relations where
     * the foreign key is on the base table.
     */
    protected function belongs_to($associated_class_name, $foreign_key_name = null)
    {
        $associated_table_name = self::_get_table_name($associated_class_name);
        $foreign_key_name = self::_build_foreign_key_name($foreign_key_name, $associated_table_name);
        $associated_object_id = $this->$foreign_key_name;

        return self::factory($associated_class_name)->where_id_is($associated_object_id);
    }

    /**
     * Helper method to manage many-to-many relationships via an intermediate model. See
     * README for a full explanation of the parameters.
     */
    protected function has_many_through($associated_class_name, $join_class_name = null, $key_to_base_table = null, $key_to_associated_table = null)
    {
        $base_class_name = get_class($this);

        // The class name of the join model, if not supplied, is
        // formed by concatenating the names of the base class
        // and the associated class, in alphabetical order.
        if (is_null($join_class_name))
        {
            $class_names = array($base_class_name, $associated_class_name);
            sort($class_names, SORT_STRING);
            $join_class_name = join("", $class_names);
        }

        // Get table names for each class
        $base_table_name = self::_get_table_name($base_class_name);
        $associated_table_name = self::_get_table_name($associated_class_name);
        $join_table_name = self::_get_table_name($join_class_name);

        // Get ID column names
        $base_table_id_column = self::_get_id_column_name($base_class_name);
        $associated_table_id_column = self::_get_id_column_name($associated_class_name);

        // Get the column names for each side of the join table
        $key_to_base_table = self::_build_foreign_key_name($key_to_base_table, $base_table_name);
        $key_to_associated_table = self::_build_foreign_key_name($key_to_associated_table, $associated_table_name);

        return self::factory($associated_class_name)->select("{$associated_table_name}.*")->join($join_table_name, array("{$associated_table_name}.{$associated_table_id_column}", '=', "{$join_table_name}.{$key_to_associated_table}"))->where("{$join_table_name}.{$key_to_base_table}", $this->id());
    }

    /**
     * Set the wrapped ORM instance associated with this Model instance.
     */
    public function set_orm($orm)
    {
        $this->orm = $orm;
    }

    /**
     * Magic getter method, allows $model->property access to data.
     */
    public function __get($property)
    {
        return $this->orm->get($property);
    }

    /**
     * Magic setter method, allows $model->property = 'value' access to data.
     */
    public function __set($property, $value)
    {
        $this->orm->set($property, $value);
    }

    /**
     * Magic isset method, allows isset($model->property) to work correctly.
     */
    public function __isset($property)
    {
        return $this->orm->__isset($property);
    }

    /**
     * Getter method, allows $model->get('property') access to data
     */
    public function get($property)
    {
        return $this->orm->get($property);
    }

    /**
     * Setter method, allows $model->set('property', 'value') access to data.
     *
     * @param string|array $key
     * @param string|null $value
     */
    public function set($property, $value = null)
    {
        $this->orm->set($property, $value);
    }

    /**
     * Setter method, allows $model->set_expr('property', 'value') access to data.
     *
     * @param string|array $key
     * @param string|null $value
     */
    public function set_expr($property, $value = null)
    {
        $this->orm->set_expr($property, $value);
    }

    /**
     * Check whether the given field has changed since the object was created or saved
     */
    public function is_dirty($property)
    {
        return $this->orm->is_dirty($property);
    }

    /**
     * Check whether the model was the result of a call to create() or not
     * @return bool
     */
    public function is_new()
    {
        return $this->orm->is_new();
    }

    /**
     * Wrapper for Idiorm's as_array method.
     */
    public function as_array()
    {
        $args = func_get_args();

        return call_user_func_array(array($this->orm, 'as_array'), $args);
    }

    /**
     * Save the data associated with this model instance to the database.
     */
    public function save()
    {
        return $this->orm->save();
    }

    /**
     * Delete the database row associated with this model instance.
     */
    public function delete()
    {
        return $this->orm->delete();
    }

    /**
     * Get the database ID of this model instance.
     */
    public function id()
    {
        return $this->orm->id();
    }

    /**
     * Hydrate this model instance with an associative array of data.
     * WARNING: The keys in the array MUST match with columns in the
     * corresponding database table. If any keys are supplied which
     * do not match up with columns, the database will throw an error.
     */
    public function hydrate($data)
    {
        $this->orm->hydrate($data)->force_all_dirty();
    }
}